Is it obligatory to dispose of money acquired from smuggling bribes, and how is that done if it is impossible to return it to its owners or if they refuse to take it, and is it permissible to give it to a charitable organization or to help a indebted brother?

The permissibility of tax evasion depends on the permissibility of the tax itself. If the tax is permissible, then evasion is not allowed. If it is impermissible, then it is allowed. If the taxes are impermissible, then there is no right to the money taken in exchange for assisting in their evasion, and it must be returned to its owners, unless they permit otherwise. If the owners of the money are unknown, then it should be given as charity on their behalf. However, if the taxes are permissible, then assisting others in evading them is not allowed, and the money taken in this case is considered a bribe, which cannot be benefited from. It must be paid to the state treasury. If that is not possible, it should be spent on public interests or given to the poor and needy. It is permissible to give this money to the poor, including poor relatives. The money that must be disposed of is the original amount that was owed by its owner.